Electronic devices, and particularly portable electronic devices such as mobile telephones and tablet computing devices, are becoming increasingly popular. Many television watchers use an electronic device while separately watching video content on the television. If the video content that the user is watching on the television is known, then secondary content related to the video content may be displayed to the user on the electronic device. In this case, the electronic device is sometime referred to as a “second screen.” The secondary content may include advertisements, product promotions, voting or polling interfaces to seek feedback from the user, sporting event statistics, etc.
But determining the video content that the user is watching on the television remains a challenge. Even more challenging is determining the portion of the video content that the user is observing at a given point in time and determining relevant secondary content that has some logical relationship to the video content.